Inline functions might not be recompiled properly

Apologies if this has been reported before, I couldn’t find it in other issues.

Changing strings in inline functions don’t seem to always be recompiled. Other changes does get recompiled.

Repro steps

Create solution with a console app and a class library:

open lib

Say.hello "there"

namespace lib

module Say =
    let inline hello name =
        printfn "Hello %s" name

Changes to the string in hello don’t apply when doing a dotnet run on the console app.

Expected behavior

Class library to be recompiled.

Actual behavior

~/dev/playground/InlineBug/console
λ dotnet run
Hello there
~/dev/playground/InlineBug/console
λ /bin/cat ../lib/Library.fs
namespace lib

module Say =
    let inline hello name =
        printfn "Bye %s" name
~/dev/playground/InlineBug/console
λ dotnet run
Hello there

Known workarounds

Doing a dotnet clean before dotnet run works.

Related information

Provide any related information (optional):

Operating system:

λ sw_vers
ProductName:		macOS
ProductVersion:		13.4.1
BuildVersion:		22F82

.NET SDK version:

7.0.306

[sualitu]

Great work, fantastic! I’m glad to hear it’s already been fixed, and I’ll be looking forward to it being released in net8. And thanks a bunch for the workaround as well.

[T-Gro]

Repro works on my end as well, not related to macOS.

• Does not matter weather the function is inline or not

• Repros both net7 as well net8

• It does get fixed when I add the <ProduceReferenceAssembly>false</ProduceReferenceAssembly> item to lib’s .fsproj!

• Independently, it also does get fixed when I add the -c Release switch to dotnet run

• When I add the -c Debug, it does not update

=> It is a combination of ProduceReferenceAssembly=true and Configuration=Debug (fsc.exe is then called with --optimize-)

What I also tested:

• I locally build the compiler tools from main
• I added the following Directory.Build.props to make use of them for dotnet run:

<Project>
    <PropertyGroup>  
        <DisableAutoSetFscCompilerPath>true</DisableAutoSetFscCompilerPath>
        <FscToolPath>$([System.IO.Path]::GetDirectoryName('$(DOTNET_HOST_PATH)'))</FscToolPath>
        <FscToolExe >dotnet.exe</FscToolExe>
        <DotnetFscCompilerPath>D:\fsharp\artifacts\bin\fsc\Release\net7.0\fsc.dll</DotnetFscCompilerPath>
    </PropertyGroup>  
</Project>

• With that, I verified that latest main correctly detects change:
  • for unspecified dotnet run
  • for dotnet run -c Debug
  • for dotnet run -c Release

=> A workaround for now is to use <ProduceReferenceAssembly>false</ProduceReferenceAssembly>. The next update of the net8 sdk will also include the change which fixes this behavior.